This 2010 WPF report, The One Way Mirror Society, explores new forms of sophisticated digital signage networks and their privacy implications in the US and other countries. Digital signage networks are being deployed widely by retailers and others in both public and private spaces. From simple people-counting sensors mounted on doorways to sophisticated facial recognition cameras mounted in flat video screens and end-cap displays, digital signage technologies are gathering increasing amounts of detailed information about consumers, their behaviors, and their characteristics.
The digital signage networks this report addresses are bi-directional. These networks give information to viewers while they capture information from viewers and send it back to a home base. In the digital signage industry, the new technologies are often compared to the interactive signs from the movie Minority Report.  In the movie, large-screen video billboards recognized individual consumers and delivered personalized advertisements to each person. The movie version of the digital signs and billboards relied on an iris scan to customize the ads. Today’s modern digital signs rely on advanced video analytics and sophisticated cameras and sensors.
The best way to understand the capabilities of digital signage today and how it is being used is to see the digital signage industry’s newly minted Recommended Code of Conduct for Consumer Tracking Methods (See Appendix A for complete document). This document on consumer tracking methods in digital signage was written and agreed upon entirely by industry members, without any participation by consumer representatives. The document reflects the advances in technology in this area and where the possibilities for abuse lay. The opening of the document reads:
Heat maps and path tracking technologies essentially generate maps of where consumers spend the most time standing and walking in stores. (Figure 2). One product, PathTracker, uses RFID chips for large store tracking, and video tracking technology for smaller stores or sub-areas within stores.
Facial recognition technology was initially developed for security purposes, but it has found a new use in digital signage for marketing and ad targeting purposes. Essentially, the process is that a camera captures an individual’s image, then checks it against algorithms that analyze at least 80 facial characteristics, such as distance between eyes, length of the face, width of the face, depth of eye sockets, and so forth.  Layers of algorithms are used to crunch the facial information into determinations about a person’s age bracket, gender, and ethnicity. The next efforts are going toward coding the facial expressions of shoppers to “capture their emotional reactions to in-store environments.”